package tree;import java.util.HashMap;import java.util.concurrent.CountDownLatch;import java.util.concurrent.Semaphore;/** * @Description: * @Date: 2020/5/28 00:31 * @Auther: zql */public class Test {    public static void main(String[] args) {        double d = 0.3d;        System.out.println(d-0.1);    }}